drivers/gpio/gpiolib.h

   1 /*
   2  * Internal GPIO functions.
   3  *
   4  * Copyright (C) 2013, Intel Corporation
   5  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #ifndef GPIOLIB_H
  13 #define GPIOLIB_H
  14
  15 #include <linux/err.h>
  16 #include <linux/device.h>
  17
  18 enum of_gpio_flags;
  19
  20 /**
  21  * struct acpi_gpio_info - ACPI GPIO specific information
  22  * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
  23  * @active_low: in case of @gpioint, the pin is active low
  24  */
  25 struct acpi_gpio_info {
  26         bool gpioint;
  27         bool active_low;
  28 };
  29
  30 #ifdef CONFIG_ACPI
  31 void acpi_gpiochip_add(struct gpio_chip *chip);
  32 void acpi_gpiochip_remove(struct gpio_chip *chip);
  33
  34 void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
  35 void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
  36
  37 struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
  38                                           const char *propname, int index,
  39                                           struct acpi_gpio_info *info);
  40 #else
  41 static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
  42 static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
  43
  44 static inline void
  45 acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
  46
  47 static inline void
  48 acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
  49
  50 static inline struct gpio_desc *
  51 acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname,
  52                         int index, struct acpi_gpio_info *info)
  53 {
  54         return ERR_PTR(-ENOSYS);
  55 }
  56 #endif
  57
  58 struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
  59                    const char *list_name, int index, enum of_gpio_flags *flags);
  60
  61 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
  62
  63 extern struct spinlock gpio_lock;
  64 extern struct list_head gpio_chips;
  65
  66 struct gpio_desc {
  67         struct gpio_chip        *chip;
  68         unsigned long           flags;
  69 /* flag symbols are bit numbers */
  70 #define FLAG_REQUESTED  0
  71 #define FLAG_IS_OUT     1
  72 #define FLAG_EXPORT     2       /* protected by sysfs_lock */
  73 #define FLAG_SYSFS      3       /* exported via /sys/class/gpio/control */
  74 #define FLAG_TRIG_FALL  4       /* trigger on falling edge */
  75 #define FLAG_TRIG_RISE  5       /* trigger on rising edge */
  76 #define FLAG_ACTIVE_LOW 6       /* value has active low */
  77 #define FLAG_OPEN_DRAIN 7       /* Gpio is open drain type */
  78 #define FLAG_OPEN_SOURCE 8      /* Gpio is open source type */
  79 #define FLAG_USED_AS_IRQ 9      /* GPIO is connected to an IRQ */
  80 #define FLAG_SYSFS_DIR  10      /* show sysfs direction attribute */
  81
  82 #define ID_SHIFT        16      /* add new flags before this one */
  83
  84 #define GPIO_FLAGS_MASK         ((1 << ID_SHIFT) - 1)
  85 #define GPIO_TRIGGER_MASK       (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE))
  86
  87         const char              *label;
  88 };
  89
  90 int gpiod_request(struct gpio_desc *desc, const char *label);
  91 void gpiod_free(struct gpio_desc *desc);
  92
  93 /*
  94  * Return the GPIO number of the passed descriptor relative to its chip
  95  */
  96 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
  97 {
  98         return desc - &desc->chip->desc[0];
  99 }
 100
 101 /* With descriptor prefix */
 102
 103 #define gpiod_emerg(desc, fmt, ...)                                            \
 104         pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 105                  ##__VA_ARGS__)
 106 #define gpiod_crit(desc, fmt, ...)                                             \
 107         pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 108                  ##__VA_ARGS__)
 109 #define gpiod_err(desc, fmt, ...)                                              \
 110         pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
 111                  ##__VA_ARGS__)
 112 #define gpiod_warn(desc, fmt, ...)                                             \
 113         pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 114                  ##__VA_ARGS__)
 115 #define gpiod_info(desc, fmt, ...)                                             \
 116         pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
 117                  ##__VA_ARGS__)
 118 #define gpiod_dbg(desc, fmt, ...)                                              \
 119         pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
 120                  ##__VA_ARGS__)
 121
 122 /* With chip prefix */
 123
 124 #define chip_emerg(chip, fmt, ...)                                      \
 125         pr_emerg("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 126 #define chip_crit(chip, fmt, ...)                                       \
 127         pr_crit("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 128 #define chip_err(chip, fmt, ...)                                        \
 129         pr_err("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 130 #define chip_warn(chip, fmt, ...)                                       \
 131         pr_warn("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 132 #define chip_info(chip, fmt, ...)                                       \
 133         pr_info("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 134 #define chip_dbg(chip, fmt, ...)                                        \
 135         pr_debug("GPIO chip %s: " fmt, chip->label, ##__VA_ARGS__)
 136
 137 #ifdef CONFIG_GPIO_SYSFS
 138
 139 int gpiochip_export(struct gpio_chip *chip);
 140 void gpiochip_unexport(struct gpio_chip *chip);
 141
 142 #else
 143
 144 static inline int gpiochip_export(struct gpio_chip *chip)
 145 {
 146         return 0;
 147 }
 148
 149 static inline void gpiochip_unexport(struct gpio_chip *chip)
 150 {
 151 }
 152
 153 #endif /* CONFIG_GPIO_SYSFS */
 154
 155 #endif /* GPIOLIB_H */